A standard baler such as described in German Patent document No. 3,445,050 makes large bales of cylindrical shape, so-called "round" bales, as opposed to smaller bales of parallepipedal shape, so called "square bales". Such a round baler comprises a housing normally displaceable in a travel direction along the ground and forming a rotary baling chamber, guides forming relative to the direction a passage having a forwardly opening front end and a rear end opening rearward into the chamber, and a pickup device forward of the passage for picking a strand of crop up off the ground and feeding it up and back to the front end of the passage. A conveyor has arms engageable downward into the passage between its ends and movable backward in the passage to advance the strand of crop backward in the passage to the baling chamber where rollers or the like wind up the strand into a cylindrical bale. To tenderize the strand and make it easier to roll up a cutter has a plurality of blades engageable upward into the passage generally at the conveyor for forming a generally random array of longitudinal slits in the strand in the passage. Unfortunately in some locations these slits are so dense that they excessively weaken the bale and that in other locations are so sparse that it is very difficult to get the crop off the bale, necessitating the use of a machine of the type described in German utility model No. 7,812,292.